*{
    margin: 0;
    padding: 0;
}
#list:before,:after{
    content: "";
    display: block;
    clear: both;
}
#btn{
    float: right;
}
#list div img {
    display: block;
    float: left;
    width: 100%;
}
#list div{
    width: 200px;
    float: left;
}
.header-a{
    padding: 10px 60px;
}
.header{
    padding-top: 10px;
}
.list-a{
    padding: 50px 50px;
}
.list-a div div {
    padding: 10px 50px;
}